Called Juno, the mission will be the first in which a spacecraft is placed in a highly elliptical polar orbit around the giant planet to understand its formation, evolution and structure. Underneath its dense cloud cover, Jupiter safeguards secrets to the fundamental processes and conditions that governed our early solar system.

"Jupiter is the archetype of giant planets in our solar system and formed very early, capturing most of the material left after the sun formed," said Scott Bolton, Juno principal investigator from the Southwest Research Institute in San Antonio. "Unlike Earth, Jupiter's giant mass allowed it to hold onto its original composition, providing us with a way of tracing our solar system's history."

The spacecraft is scheduled to launch aboard an Atlas rocket from Cape Canaveral, Fla., in August 2011, reaching Jupiter in 2016. The spacecraft will orbit Jupiter 32 times, skimming about 4,800 kilometers (3,000 miles) over the planet's cloud tops for approximately one year. The mission will be the first solar powered spacecraft designed to operate despite the great distance from the sun.

"Jupiter is more than 644 million kilometers (400 million miles) from the sun or five times further than Earth," Bolton said. "Juno is engineered to be extremely energy efficient."

The spacecraft will use a camera and nine science instruments to study the hidden world beneath Jupiter's colorful clouds. The suite of science instruments will investigate the existence of an ice-rock core, Jupiter's intense magnetic field, water and ammonia clouds in the deep atmosphere, and explore the planet's aurora borealis.

"In Greek and Roman mythology, Jupiter's wife Juno peered through Jupiter's veil of clouds to watch over her husband's mischief," said Professor Toby Owen, co-investigator at the University of Hawaii in Honolulu. "Our Juno looks through Jupiter's clouds to see what the planet is up to, not seeking signs of misbehavior, but searching for whispers of water, the ultimate essence of life."

Understanding the formation of Jupiter is essential to understanding the processes that led to the development of the rest of our solar system and what the conditions were that led to Earth and humankind. Similar to the sun, Jupiter is composed mostly of hydrogen and helium. A small percentage of the planet is composed of heavier elements. However, Jupiter has a larger percentage of these heavier elements than the sun.

"Juno's extraordinarily accurate determination of the gravity and magnetic fields of Jupiter will enable us to understand what is going on deep down in the planet," said Professor Dave Stevenson, co-investigator at the California Institute of Technology in Pasadena. "These and other measurements will inform us about how Jupiter's constituents are distributed, how Jupiter formed and how it evolved, which is a central part of our growing understanding of the nature of our solar system."

Deep in Jupiter's atmosphere, under great pressure, hydrogen gas is squeezed into a fluid known as metallic hydrogen. At these great depths, the hydrogen acts like an electrically conducting metal which is believed to be the source of the planet's intense magnetic field. Jupiter also may have a rocky solid core at the center.

"Juno gives us a fantastic opportunity to get a picture of the structure of Jupiter in a way never before possible," said James Green, director of NASA's Planetary Division at NASA Headquarters in Washington. "It will allow us to take a giant step forward in our understanding on how giant planets form and the role that plays in putting the rest of the solar system together. "

The Juno mission is the second spacecraft designed under NASA's New Frontiers Program. The first was the Pluto New Horizons mission, launched in January 2006 and scheduled to reach Pluto's moon Charon in 2015. The program provides opportunities to carry out several medium-class missions identified as top priority objectives in the Decadal Solar System Exploration Survey, conducted by the Space Studies Board of the National Research Council in Washington.

NASA's Jet Propulsion Laboratory in Pasadena, Calif., manages the Juno mission. Lockheed Martin of Denver is building the spacecraft. The Italian Space Agency is contributing an infrared spectrometer instrument and a portion of the radio science experiment.

Robert PearlmanEditor

Posts: 28309From: Houston, TXRegistered: Nov 1999

posted 04-09-2011 09:04 PM
NASA release

NASA's Jupiter-Bound Spacecraft Arrives in Florida

NASA's Juno spacecraft has arrived in Florida to begin final preparations for a launch this summer. The spacecraft was shipped from Lockheed Martin Space Systems, Denver, to the Astrotech payload processing facility in Titusville, Fla., today. The solar-powered Juno spacecraft will orbit Jupiter's poles 33 times to find out more about the gas giant's origins, structure, atmosphere and magnetosphere.

"The Juno spacecraft and the team have come a long way since this project was first conceived in 2003," said Scott Bolton, Juno's principal investigator, based at Southwest Research Institute in San Antonio. "We're only a few months away from a mission of discovery that could very well rewrite the books on not only how Jupiter was born, but how our solar system came into being."

Next Monday, Juno will be removed from its shipping container, the first of the numerous milestones to prepare it for launch. Later that week, the spacecraft will begin functional testing to verify its state of health after the road trip from Colorado. After this, the team will load updated flight software and perform a series of mission readiness tests. These tests involve the entire spacecraft flight system, as well as the associated science instruments and the ground data system.

Juno will be carried into space aboard a United Launch Alliance Atlas V rocket lifting off from Launch Complex-41 at the Cape Canaveral Air Force Station in Florida. The launch period opens Aug. 5, 2011, and extends through Aug. 26. For an Aug. 5 liftoff, the launch window opens at 8:39 a.m. PDT (11:39 am EDT) and remains open through 9:39 a.m. PDT (12:39 p.m. EDT).

NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Juno mission for the principal investigator, Scott Bolton, of Southwest Research Institute at San Antonio. The Juno mission is part of the New Frontiers Program managed at NASA's Marshall Space Flight Center in Huntsville, Ala. Lockheed Martin Space Systems, Denver, is building the spacecraft. The Italian Space Agency in Rome is contributing an infrared spectrometer instrument and a portion of the radio science experiment. Launch management for the mission is the responsibility of NASA's Launch Services Program at the Kennedy Space Center in Florida. JPL is a division of the California Institute of Technology in Pasadena.

Robert PearlmanEditor

Posts: 28309From: Houston, TXRegistered: Nov 1999

posted 07-27-2011 10:00 AM

Juno spacecraft encased for launch

In the Astrotech payload processing facility near the Kennedy Space Center in Florida, an Atlas payload fairing was closed around NASA's Juno spacecraft on July 18, 2011.

The fairing was then moved on July 25 onto a transporter for its trip to Space Launch Complex 41 at the Cape Canaveral Air Force Station.

The fairing will protect the spacecraft from the impact of aerodynamic pressure and heating during ascent and will be jettisoned once the spacecraft is outside the Earth's atmosphere. Juno is scheduled to launch aboard a United Launch Alliance (ULA) Atlas V on August 5.

Credit: NASA/Kim Shiflett/Frank Michaux

Robert PearlmanEditor

Posts: 28309From: Houston, TXRegistered: Nov 1999

posted 07-27-2011 01:38 PM
NASA release

NASA's Jupiter-Bound Juno Mated to Its Rocket

NASA's Juno spacecraft completed its last significant terrestrial journey on Wednesday, with a 15-mile (25-kilometer) trip from Astrotech Space Operations in Titusville, Fla., to its launch pad at the Cape Canaveral Air Force Station. The solar-powered, Jupiter-bound spacecraft was secured into place on top of its rocket at 10:42 a.m. EDT (7:42 a.m. PDT).

Juno will arrive at Jupiter in July 2016 and orbit its poles 33 times to learn more about the gas giant's interior, atmosphere and aurora.

"We're about to start our journey to Jupiter to unlock the secrets of the early solar system," said Scott Bolton, the mission's principal investigator from the Southwest Research Institute in San Antonio. "After eight years of development, the spacecraft is ready for its important mission."

Now that the Juno payload is atop the most powerful Atlas rocket ever made -- the United Launch Alliance Atlas V 551 -- a final flurry of checks and tests can begin and confirm that all is go for launch. The final series of checks begins Wednesday with an on-pad functional test. The test is designed to confirm that the spacecraft is healthy after the fueling, encapsulation and transport operations.

"The on-pad functional test is the first of seven tests and reviews that Juno and its flight team will undergo during the spacecraft's last 10 days on Earth," said Jan Chodas, Juno's project manager at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, Calif. "There are a number of remaining prelaunch activities that we still need to focus on, but the team is really excited that the final days of preparation, which we've been anticipating for years, are finally here. We are ready to go."

The launch period for Juno opens Aug. 5, 2011, and extends through Aug. 26. For an Aug. 5 liftoff, the launch window opens at 11:34 a.m. EDT and remains open through 12:43 EDT.

JPL manages the Juno mission for principal investigator Scott Bolton. The Juno mission is part of the New Frontiers Program managed at NASA's Marshall Space Flight Center in Huntsville, Ala. Lockheed Martin Space Systems of Denver built the spacecraft. Launch management for the mission is the responsibility of NASA's Launch Services Program at the agency's Kennedy Space Center in Florida. JPL is a division of the California Institute of Technology in Pasadena.

Robert PearlmanEditor

Posts: 28309From: Houston, TXRegistered: Nov 1999

posted 08-04-2011 01:32 PM

Atlas V rolled out for Juno launch

A United Launch Alliance Atlas V rocket with the Juno spacecraft rolled out to the Space Launch Complex (SLC)-41 launch pad at 9 a.m. EDT Thursday (Aug. 4). The launch of the Juno mission is set for Friday, Aug. 5 with the launch period opening at 11:34 a.m. EDT.

Credit: ULA/Pat Corkery

Robert PearlmanEditor

Posts: 28309From: Houston, TXRegistered: Nov 1999

posted 08-05-2011 07:35 AM

Launch Day for Juno

The countdown is moving ahead this morning toward a liftoff at 11:34 a.m. EDT (1534 GMT) to begin the Juno mission to Jupiter.

The United Launch Alliance (ULA) Atlas V rocket carrying the four-ton spacecraft is poised at Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida within sight of the space shuttle launch pads to the north.

The last probe to fly to Jupiter, Galileo, was sent aloft aboard a space shuttle in 1989. Juno's mission was inspired in part to search for answers to questions raised by Galileo's findings.

The weather forecast is positive this morning and there are no indications of technical issues.

Robert PearlmanEditor

Posts: 28309From: Houston, TXRegistered: Nov 1999

posted 08-05-2011 09:03 AM

Atlas V tanks fueling

The fuel and oxygen tanks in the Atlas V and Centaur upper stage are being loaded with propellants this morning as the countdown for the launch of the Juno spacecraft to Jupiter proceeds on pace for a 11:34 a.m. EDT (1534 GMT) liftoff.

The Atlas V first stage operates on high-grade kerosene and liquid oxygen, while the Centaur uses liquid hydrogen for fuel along with liquid oxygen to power its engine.

There are no technical issues and the weather forecast calls for a 70 percent chance of acceptable conditions.

Robert PearlmanEditor

Posts: 28309From: Houston, TXRegistered: Nov 1999

posted 08-05-2011 10:39 AM

Launch on hold at T-4 minutes for technical issue

The launch of NASA's Juno spacecraft has been delayed as the Atlas V launch team works an issue with higher than expected cycles of the Centaur upper stage's helium charge system.

The launch team is reviewing the cycle rate as compared to a launch countdown rehearsal held a couple of weeks ago, and is performing a leak check.

UPDATE: The leak check has been called off as the Centaur helium problem appears to be isolated to the ground-side of the system (as opposed to an issue with the launch vehicle). The team switched to a secondary helium system to clear the issue.

The launch team is now attempting to clear the range of any boats that may have strayed into the hazard area off the coast of Cape Canaveral.

The launch window extends today until 12:43 p.m. EDT (1643 GMT). The countdown is being held at the T-minus 4 minute mark.

Robert PearlmanEditor

Posts: 28309From: Houston, TXRegistered: Nov 1999

posted 08-05-2011 10:59 AM

Helium issue cleared, launch time reset

Having cleared an issue with the Atlas V's Centaur upper stage and cleared the range of wayward boats, the launch team has re-targeted today's launch of NASA's Juno spacecraft for 12:25 p.m. EDT (1625 GMT).

"Liftoff of the Atlas V with Juno on a trek to Jupiter. A planetary piece of the puzzle on the beginning of our solar system."

— NASA launch commentator George Diller

NASA's Juno spacecraft lifted off from the Cape Canaveral Air Force Station at 12:25 p.m. EDT Friday (Aug. 5) to begin a five-year journey to Jupiter.

Juno's detailed study of the largest planet in our solar system will help reveal Jupiter's origin and evolution. As the archetype of giant gas planets, Jupiter can help scientists understand the origin of our solar system and learn more about planetary systems around other stars.

"Today, with the launch of the Juno spacecraft, NASA began a journey to yet another new frontier," NASA's Administrator Charles Bolden said. "The future of exploration includes cutting-edge science like this to help us better understand our solar system and an ever increasing array of challenging destinations."

After Juno's launch aboard an Atlas V rocket, mission controllers now await telemetry from the spacecraft indicating it has achieved its proper orientation, and that its massive solar arrays, the biggest on any NASA deep-space probe, have deployed and are generating power.

"We are on our way, and early indications show we are on our planned trajectory," said Jan Chodas, Juno project manager at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, Calif. "We will know more about Juno's status in a couple hours after its radios are energized and the signal is acquired by the Deep Space Network antennas at Canberra."

Credit: NASA/Bill Ingalls

Juno will cover the distance from Earth to the moon (about 250,000 miles or 402,236 kilometers) in less than one day's time. It will take another five years and 1,740 million miles (2,800 million kilometers) to complete the journey to Jupiter.

Juno will orbit the planet's poles 33 times and use its collection of eight science instruments to probe beneath the gas giant's obscuring cloud cover to learn more about its origins, structure, atmosphere, and magnetosphere, and look for a potential solid planetary core.

With four large moons and many smaller moons, Jupiter forms its own miniature solar system. Its composition resembles a star's, and if it had been about 80 times more massive, the planet could have become a star instead.

Credit: ULA/Pat Corkery

"Jupiter is the Rosetta Stone of our solar system," said Scott Bolton, Juno's principal investigator from the Southwest Research Institute in San Antonio. "It is by far the oldest planet, contains more material than all the other planets, asteroids and comets combined and carries deep inside it the story of not only the solar system but of us. Juno is going there as our emissary — to interpret what Jupiter has to say."

Juno's name comes from Greek and Roman mythology. The god Jupiter drew a veil of clouds around himself to hide his mischief, and his wife, the goddess Juno, was able to peer through the clouds and reveal Jupiter's true nature.

Robert PearlmanEditor

Posts: 28309From: Houston, TXRegistered: Nov 1999

posted 08-05-2011 12:30 PM

Juno flying on its own to Jupiter

At 53 minutes and 14 seconds into its flight (1:18 p.m. EDT), the Juno spacecraft successfully separated from the Centaur upper stage and is now on its own on a path to Jupiter.

"Flight so far looks fantastic," NASA launch manager Omar Baez said, adding that Juno is in the right orbit to start its journey to Jupiter. "We're right on track for that, and everything looked good."

Juno has deployed its three tractor-trailer-size solar arrays. Each array is 29.5 feet long and 8.7 feet wide. There are 18,698 solar cells on the panels to generate approximately 400 watts of electricity once at Jupiter.

Robert PearlmanEditor

Posts: 28309From: Houston, TXRegistered: Nov 1999

posted 08-30-2011 08:52 PM

Jupiter-bound Juno captures Earth and moon

On its way to the biggest planet in the solar system — Jupiter, NASA's Juno spacecraft took time to capture its home planet and its natural satellite — the moon.

"This is a remarkable sight people get to see all too rarely," said Scott Bolton, Juno principal investigator from the Southwest Research Institute in San Antonio. "This view of our planet shows how Earth looks from the outside, illustrating a special perspective of our role and place in the universe. We see a humbling yet beautiful view of ourselves."

The image was taken by the spacecraft's camera, JunoCam, on Aug. 26 when the spacecraft was about 6 million miles (9.66 million kilometers) away. The image was taken as part of the mission team's checkout of the Juno spacecraft. The team is conducting its initial detailed checks on the spacecraft's instruments and subsystems after its launch on Aug. 5.

Juno covered the distance from Earth to the moon (about 250,000 miles or 402,000 kilometers) in less than one day's time. It will take the spacecraft another five years and 1,740 million miles (2,800 million kilometers) to complete the journey to Jupiter.

The spacecraft will orbit the planet's poles 33 times and use its eight science instruments to probe beneath the gas giant's obscuring cloud cover to learn more about its origins, structure, atmosphere and magnetosphere, and look for a potential solid planetary core.

The solar-powered Juno spacecraft lifted off from Cape Canaveral Air Force Station in Florida at 9:25 a.m. PDT (12:25 p.m. EDT) on Aug. 5 to begin its five-year journey to Jupiter.

Robert PearlmanEditor

Posts: 28309From: Houston, TXRegistered: Nov 1999

posted 09-05-2012 08:02 PM

Juno maneuvering for Earth flyby

Navigators and mission controllers for NASA's Juno mission to Jupiter have decided to reschedule the mission's second deep space maneuver for Sept. 14. The maneuver will set the stage for a gravity assist from a flyby of Earth on Oct. 9, 2013. Juno will arrive at Jupiter on July 4, 2016.

Juno's first deep space maneuver took place Aug. 30. The maneuver, as planned, changed the spacecraft's velocity by about 770 mph (344 meters a second) and lasted 29 minutes 39 seconds. Upon review of mission data following the burn, the team determined that although the first maneuver was completely successful, one of the propellant pressures within the spacecraft's propulsion system was higher than expected. The team has decided to take an extra 10 days to analyze this increase and consider mitigation options, placing the second deep space maneuver on Sept. 14. There will be no impact to the mission's timeline or science.

The two deep space maneuvers place Juno on course for its Earth flyby, which will occur as the spacecraft is completing one elliptical orbit around the sun. The Earth flyby will boost Juno's velocity by 16,330 mph (about 7.3 kilometers per second), placing the spacecraft on its final flight path for Jupiter. The closest approach to Earth on Oct. 9, 2013, will occur when Juno is at an altitude of about 310 miles (500 kilometers).

"Juno's odometer just clicked over to 9.464 astronomical units," said Juno Principal Investigator Scott Bolton, of the Southwest Research Institute in San Antonio. "The team is looking forward, preparing for the day we enter orbit around the most massive planet in our solar system."

For those astronomical-unitly challenged, an astronomical unit (AU) is a unit of measure used by space engineers and scientists when discussing the massive distances involved in the exploration of our solar system – and beyond. An AU is based on the distance between Earth and the sun and is 92,955,807.273 miles (149,597,870.7 kilometers) long. The 9.464 astronomical units Juno has already traveled (or still has left to go) is equivalent to 879,733,760 miles (or 1,415,794,248 kilometers). Juno was 34.46 million miles (55.46 million kilometers) from Earth when the milestone was reached.

The next milestone in the nearly five-year journey to Jupiter will occur this October, when the spacecraft flies past Earth in search of a little extra speed.

"On Oct. 9, Juno will come within 347 miles (559 kilometers) of Earth," said the mission's Project Manager Rick Nybakken of NASA's Jet Propulsion Laboratory in Pasadena, Calif. "The Earth flyby will give Juno a kick in the pants, boosting its velocity by 16,330 mph (about 7.3 kilometers per second). From there, it's next stop Jupiter."

Juno will arrive at Jupiter on July 4, 2016, at 9:29 p.m. CDT (0229 GMT July 5).

Juno was launched on Aug. 5, 2011. Once in orbit around Jupiter, the spacecraft will circle the planet 33 times, from pole to pole, and use its collection of eight science instruments to probe beneath the gas giant's obscuring cloud cover. Juno's science team will learn about Jupiter's origins, structure, atmosphere and magnetosphere, and look for a potential solid planetary core.

Juno's name comes from Greek and Roman mythology. The god Jupiter drew a veil of clouds around himself to hide his mischief, and his wife, the goddess Juno, was able to peer through the clouds and reveal Jupiter's true nature.

Before it reaches its destination, Juno will greet the Earth one last time. The spacecraft will perform a flyby Oct. 9, passing within 347 miles of Earth.

The flyby will function as a gravity assist for Juno, with Earth's gravity accelerating the solar-powered spacecraft's velocity by 16,330 miles per hour. NASA launched Juno to an area just past Mars, then two main engine burns executed a year ago maneuvered it back around toward Earth.

The purpose of using a gravity assist to get Juno on its way to Jupiter is one of cost.

"A direct mission to Jupiter would have required about 50 percent more fuel than we loaded," said Tim Gasparrini, Juno program manager for Lockheed Martin Space Systems. "Had we not chosen to do the flyby, the mission would have required a bigger launch vehicle, a larger spacecraft and would have been more expensive."

Lockheed Martin's Juno team is playing an active and varied role in the mission and is preparing for the flyby.

"While flying Juno is a team effort, the core operations are in Denver," said Gasparrini. "We are responsible for systems engineering, subsystem performance and execution of the commanding that goes to the Juno spacecraft. During the flyby, the team will be monitoring the spacecraft because gravity is doing all the work."

NASA's Jet Propulsion Laboratory is providing the critical navigation for the mission and the flyby.

In the lead up to the flyby, Gasparrini's team has been active monitoring Juno.

"We've been doing final reviews on sequences necessary to conduct the flyby," said Jeff Lewis, spacecraft engineer and Lockheed Martin Space Systems operations lead for Juno. "Most of the commanding is folded into our 28-day background sequence, and most of the sequences started on Sept. 27."

For Lewis and others on the team, a big part of positioning Juno for a successful gravity assist is to ensure the spacecraft steers clear of other objects in its vicinity.

"The day of the Earth flyby, the team will be on hand to monitor things," said Lewis. "We have a couple of possible collision avoidance maneuvers to select from, looking at all the satellites around the Earth. We are passing inside the orbits of geostationary spacecraft."

Catching a velocity boost isn't the only value in the effort. The operation also will permit officials to test Juno's instruments and observe the spacecraft's flight handling.

"We'll exercise the science instruments, since Juno's instruments will be operating in a magnetospheric environment for the first time," said Lewis. "The Earth's magnetic field will allow a number of the instruments to be tested. We're also using the flyby of the moon as an opportunity to gauge how the spacecraft operates. Since Juno is a spinning spacecraft, we need to sense the right time to take data as the Moon, or Jupiter, passes through the instruments' fields of view."

On Aug. 12, Juno achieved a milestone by reaching the halfway point on its trek to Jupiter as it had traveled 9.46 astronomical units, equivalent to 879,733,760 miles, at that point. Demonstrating fortuitous timing, the spacecraft is scheduled to reach Jupiter July 4, 2016.

Juno's primary mission is to study Jupiter's atmosphere as a means of better understanding how the planet, and by extension, the solar system originated and evolved. Juno will employ its suite of scientific instruments to peer beneath the planet's dense cloud cover to study the existence of a solid planetary core, map Jupiter's magnetic field, measure water content in the atmosphere and study the planet's auroras.

The spacecraft will orbit Jupiter for about one year, or 33 orbits, operating at times as close as 3,100 miles above the planet's clouds.

According to Gasparrini, the Lockheed Martin Juno team is working collaboratively with other members of the overall Juno program team to ensure mission success. Other team members include NASA, the Jet Propulsion Laboratory, the Southwest Research Institute – including Scott Bolton, Juno's principal investigator – and a number of scientists throughout the world.

As the flyby approaches, Gasparrini and team are locked in and ready.

"The team is 100 percent focused on executing the Earth flyby successfully," said Gasparrini. "We've spent a lot of time looking at possible off-nominal conditions. In the presence of a fault, the spacecraft will stay healthy and will perform as planned."

Robert PearlmanEditor

Posts: 28309From: Houston, TXRegistered: Nov 1999

posted 10-10-2013 08:06 AM

Juno enters 'safe mode' after Earth flyby

NASA's Juno probe detected an anomalous condition and went into safe mode Wednesday (Oct. 9) after slingshotting around Earth to gain momentum for the long trip to Jupiter, SPACE.com reported.

While Juno's mission managers are still attempting to discern what happened, they are hopeful that the problem won't threaten the $1.1 billion mission.

"We believe we are on track as planned to Jupiter," Juno project manager Rick Nybakken, with NASA's Jet Propulsion Laboratory, told the Associated Press, describing his level of concern as "moderate."

Data indicates the spacecraft obtained the predicted gravity boost from the flyby, Spaceflight Now reported, citing Scott Bolton, Juno's principal investigator from the Southwest Research Institute in San Antonio.

Bolton said Juno is designed to downlink data at a slower rate than normal during a safe mode, but telemetry from the spacecraft shows all its systems and instruments are fine.

Robert PearlmanEditor

Posts: 28309From: Houston, TXRegistered: Nov 1999

posted 10-12-2013 10:53 AM
Southwest Research Institute release

Juno Spacecraft Resumes Full Flight Operations on Way to Jupiter

NASA's Juno spacecraft, which is on its way to Jupiter, resumed full flight operations Friday (Oct. 11). The spacecraft had entered safe mode during its flyby of Earth on Wednesday. The safe mode did not impact the spacecraft's trajectory one smidgeon. This flyby provided the necessary gravity boost to accurately slingshot the probe towards Jupiter, where it will arrive on July 4, 2016.

The spacecraft is currently operating nominally and all systems are fully functional.

On Oct. 9, Juno past within 350 miles of the ocean just off the tip of South Africa at 2:21 p.m. CDT (1921 GMT). Soon after the closest approach, a signal was received by the European Space Agency's (ESA) 15-meter antenna just north of Perth, Australia, indicating the spacecraft initiated an automated fault-protection action called "safe mode."

Safe mode is a state that the spacecraft may enter if its on-board computer perceives conditions on the spacecraft are not as expected. Aboard Juno, the safe mode turned off instruments and a few non-critical spacecraft components, and pointed the spacecraft toward the Sun to ensure the solar arrays received power. The spacecraft acted as expected during the transition into and while in safe mode.

The Juno science team is continuing to analyze data acquired by the spacecraft's science instruments during the flyby. Most data and images were downlinked prior to the safe mode event.

Robert PearlmanEditor

Posts: 28309From: Houston, TXRegistered: Nov 1999

posted 12-10-2013 05:48 PM
NASA release

NASA's Juno Gives Starship-Like View of Earth Flyby

When NASA's Juno spacecraft flew past Earth on Oct. 9, 2013, it received a boost in speed of more than 8,800 mph (about 7.3 kilometer per second), which set it on course for a July 4, 2016, rendezvous with Jupiter, the largest planet in our solar system. One of Juno's sensors, a special kind of camera optimized to track faint stars, also had a unique view of the Earth-moon system. The result was an intriguing, low-resolution glimpse of what our world would look like to a visitor from afar.

"If Captain Kirk of the USS Enterprise said, 'Take us home, Scotty,' this is what the crew would see," said Scott Bolton, Juno principal investigator at the Southwest Research Institute, San Antonio. "In the movie, you ride aboard Juno as it approaches Earth and then soars off into the blackness of space. No previous view of our world has ever captured the heavenly waltz of Earth and moon."

The cameras that took the images for the movie are located near the pointed tip of one of the spacecraft's three solar-array arms. They are part of Juno's Magnetic Field Investigation (MAG) and are normally used to determine the orientation of the magnetic sensors. These cameras look away from the sunlit side of the solar array, so as the spacecraft approached, the system's four cameras pointed toward Earth. Earth and the moon came into view when Juno was about 600,000 miles (966,000 kilometers) away -- about three times the Earth-moon separation.

During the flyby, timing was everything. Juno was traveling about twice as fast as a typical satellite, and the spacecraft itself was spinning at 2 rpm. To assemble a movie that wouldn't make viewers dizzy, the star tracker had to capture a frame each time the camera was facing Earth at exactly the right instant. The frames were sent to Earth, where they were processed into video format.

"Everything we humans are and everything we do is represented in that view," said the star tracker's designer, John Jørgensen of the Danish Technical University, near Copenhagen.

Also during the flyby, Juno's Waves instrument, which is tasked with measuring radio and plasma waves in Jupiter's magnetosphere, recorded amateur radio signals. This was part of a public outreach effort involving ham radio operators from around the world. They were invited to say "HI" to Juno by coordinating radio transmissions that carried the same Morse-coded message. Operators from every continent, including Antarctica, participated.

"With the Earth flyby completed, Juno is now on course for arrival at Jupiter on July 4, 2016," said Rick Nybakken, Juno project manager at NASA's Jet Propulsion Laboratory in Pasadena, Calif.

The Juno spacecraft was launched from Kennedy Space Center in Florida on August 5, 2011. Juno's launch vehicle was capable of giving the spacecraft only enough energy to reach the asteroid belt, at which point the sun's gravity pulled it back toward the inner solar system. Mission planners designed the swing by Earth as a gravity assist to increase the spacecraft's speed relative to the sun, so that it could reach Jupiter. (The spacecraft's speed relative to Earth before and after the flyby is unchanged.)

After Juno arrives and enters into orbit around Jupiter in 2016, the spacecraft will circle the planet 33 times, from pole to pole, and use its collection of science instruments to probe beneath the gas giant's obscuring cloud cover. Scientists will learn about Jupiter's origins, internal structure, atmosphere and magnetosphere.

Juno's name comes from Greek and Roman mythology. The god Jupiter drew a veil of clouds around himself to hide his mischief from his wife, but the goddess Juno used her special powers to peer through the clouds and reveal Jupiter's true nature.